A second man has died in Victoria's massive bushfires and an unprecedented state of disaster has been declared for the regions most ravaged by blazes.
Victoria's Premier Daniel Andrews on Thursday night confirmed the second death in East Gippsland, but could not reveal the man's identity.
"There are still some family members that need to be talked to, that's a process that I think everybody would support," he told reporters in Melbourne. Victoria Police said the man's body was found at a property in Maramingo Creek, near Genoa, by family on Wednesday evening, reports news.com.au.
"It is believed the man suffered a medical episode while fighting the fires," they said in a statement.
Earlier on Wednesday, family members confirmed that Buchan man Mick Roberts had died at his home.
Another 17 people remain missing in East Gippsland, none of whom are emergency services personnel.
The premier noted the second death while revealing a state of disaster has been declared for six local government areas and three alpine resorts confronted by fires.
The declaration includes powers introduced in the aftermath of devastating 2009 blazes which have never been used before, including compelling people to evacuate.
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Andrews said they will send a powerful message to people in fire areas. "If you can leave, you must leave. If you don't, we simply cannot guarantee your safety," he said.
"You may well find yourself isolated and cut off for an extended period of time after fire activity." Areas covered by the declaration, which has been made for seven days, are East Gippsland Shire, Mansfield Shire, Wellington Shire, Wangaratta Rural Shire, Towong Shire and Alpine Shire.
Mount Butler, Mount Hotham and the Mount Stirling Alpine Resorts are also covered.
More than 50 fires were raging across the state on Thursday, with the worst burning predominantly in East Gippsland and the alpine region. Residents of those areas have been told they should leave, before strong winds and temperatures above 40C forecast for some areas on Saturday. "We have a small window of opportunity," Assistant Emergency Services Commissioner Deb Abbott told reporters on Thursday.
"It's a window of opportunity for those people to leave now and we want them to leave now." Though Saturday will bring the most bushfire risk, conditions will deteriorate from Friday, with authorities declared a total fire ban on Friday across East Gippsland and the Wimmera, North East and South West regions. Temperatures are expected to peak in the high 20s and winds will be light, but that does not rule out more fire danger.
"There can be significant fire activity even when conditions are fairly light in terms of winds," Bureau of Meteorology senior forecaster Tom Delamotte told AAP.
The military has arrived to provide relief and resources for fire victims across East Gippsland, as well as evacuating people from Mallacoota. About 24 communities are isolated and reaching them to deliver supplies has been difficult.
Andrews said Victoria will call on the military to provide more assistance with solutions such as tenting.
Prime Minister Scott Morrison said the federal government was offering any assistance requested.
"Our task has been to fully support and provide whatever assistance is necessary through all the various agencies of the Commonwealth," he told reporters in Sydney.
"The provision of disaster payments that have now exceeded some more than $21 million in New South Wales alone and we expect more of that to continue in Victoria as the full devastation of the fires there becomes more evident." The leader will visit East Gippsland on Friday.
Ahead of midnight on Thursday, warning levels for all Victorian fires were sitting no higher than a "watch and act" alert.
But smoky conditions have at times stopped flights to rescue people, deliver supplies and rotate firefighters.
Authorities are also concerned a fire at Corryong in Victoria's northeast could merge with another on NSW's southern border.
Corryong residents are being doorknocked and told to leave the region before the weekend.
A series of community meetings were being held on Thursday in Mallacoota, where 3000 to 4000 people remain stranded.
The navy will start evacuating Mallacoota on Friday morning, with about 1000 people to leave.
So far the fires have burnt more than 784,000 hectares in Victoria.
Meanwhile, Prime Minister Scott Morrison quickly abandoned a meet-and-greet in a bushfire-ravaged NSW town after angry locals verbally abused him.
The prime minister on Thursday visited the Bega Valley township of Cobargo, which was engulfed by flames on Tuesday morning.
NSW Premier Gladys Berejiklian declared a seven-day state of emergency that allows for forced evacuations beginning Friday, for the third time in Australia's most populated region this fire season.
"We don't take these decisions lightly but we also want to make sure we're taking every single precaution to be prepared for what could be a horrible day on Saturday," she said.
It came as the NSW Rural Fire Service declared two "tourist leave zones" stretching almost 300 kilometres (186 miles) from the town of Nowra along the picturesque coast to neighbouring Victoria state, where people are also being urged to flee.
In Canberra, an elderly woman died after a flight from Brisbane after suffering respiratory distress at Canberra Airport, which was blanketed in thick smoke from the bushfires.